Dietary antioxidant intake increases ankle brachial pressure index in men but not in women: a cross-sectional study

Objective

Atherosclerosis is a significant cause of cardiovascular and cerebrovascular diseases, with a greater impact on men than women. Dietary antioxidant intake is inversely related to the risk of atherosclerosis development. We aimed to investigate the association between dietary composite antioxidant intake and the ankle brachial pressure index (ABPI). The ABPI is not only used for assessing the progression of arterial lesions but also for stratifying the risk of atherosclerotic disease.

Methods

We conducted a cross-sectional analysis involving 1,049 participants from the National Health and Nutrition Examination Survey (NHANES). We examined six antioxidants (zinc, selenium, carotenoids, and vitamins A, C, and E) and a composite dietary antioxidant index (CDAI) derived from these antioxidants as exposure variables. The primary outcomes encompassed cardio-metabolic parameters, including body mass index (BMI), body fat mass (BFM), systolic and diastolic blood pressure, triglycerides, HDL and LDL cholesterol, C-reactive protein, and the Ankle-Brachial Pressure Index (ABPI). Associations and interactions between variables were assessed using linear regression analyses. Moreover, mediation and moderation analysis is employed.

Results

Hierarchical multiple regression analysis revealed that among men, dietary intake of zinc, selenium, and vitamin A remained positively associated with a higher ABPI even after adjusting for covariates. Conversely, in the stratified regression analysis based on CDAI quartiles, a U-shaped association between CDAI and ABPI was suggested. Notably, no significant association between dietary antioxidant intake and ABPI was observed among women. CDAI, intake of Vitamin A, Vitamin C, and Vitamin E do not influence all-cause death through mediation by abpi, but rather have a direct effect on all-cause death. Moreover, there is a significant interaction between the intake of Vitamin A and gender, where a daily intake of Vitamin A more than 776 ug is especially beneficial for women.

Conclusion

The combined intake of nutrients with antioxidant properties may prevent the initiation and progression of atherosclerosis and influence the outcome in a sex-specific manner.

Clinimetrics of the Lanarkshire Oximetry Index for patients with leg ulcers: A systematic review and meta-analysis

Ankle Brachial Pressure Index (ABPI) measurement has long been considered the gold standard of vascular assessment for people with lower limb ulceration. Despite this, only around 15% of patients in the United Kingdom who require an ABPI measurement undergo the assessment. The Lanarkshire Oximetry Index (LOI) is a cheaper and arguably more accessible approach to vascular assessment and was initially proposed as an alternative to the ABPI in 2000. No synthesis of evidence related to the LOI has been performed since its introduction into the literature. Primary studies were sought to determine the clinimetric properties of the LOI and its level of agreement with ABPI assessments. Systematic searches of MEDLINE, CINAHL, Cochrane Central Register of Controlled Trials, BNI, ProQuest Health and Medicine, Science Direct, Google Scholar and the British Library (online search) were conducted. Reference lists of identified studies were also reviewed to identify additional studies. Three primary studies met the inclusion criteria, reporting data from 307 patients and 584 limbs assessed using both the LOI and ABPI. All three studies reported fair to moderate kappa values for interrater reliability (κ = 0.290-0.747) and statistically significant positive correlation coefficients (r = 0.37, p < 0.001 in two studies) between the LOI and ABPI. The combined data from the three studies indicated a sensitivity of 52% (41.78-62.1, 95% confidence interval [CI]) and specificity of 96.08% (93.4-97.9, 95% CI) for the LOI using the ABPI as a reference. Additional data are required to indicate the safety of the LOI in practice. Data are also required to determine if the LOI is more acceptable to clinicians compared to the ABPI and whether there are any barriers/enablers to its implementation in practice. Given the relatively low specificity of the LOI, it may be beneficial to combine measurement of the LOI with a subjective clinical risk assessment tool to improve the sensitivity of this alternative approach to vascular assessment.

Outcomes following supervised exercise and home-based exercise for patients with intermittent claudication

INTRODUCTION

Intermittent claudication (IC) is the most common symptom of peripheral arterial disease (PAD) which presents as a consequence of muscle ischaemia resulting from the atherosclerotic obstruction to arterial flow. High-quality evidence (Lane et al., 2017) shows that exercise programmes provide important benefits compared with usual care in improving pain-free and maximum walking distance in people with IC, but do not improve ankle-brachial pressure index (ABPI).

METHODS

Retrospective data were analysed to examine walking and ABPI outcomes for participants who completed a 12-week course of supervised or home-based exercise. All participants had a history of IC.

RESULTS

46 participants (mean age 69±11 years; 76% male; 29% current smokers) referred for exercise were assessed, completed a 12-week course of exercise (home-based or supervised) and subsequently attended for re-assessment. Claudication onset distance (COD) increased by 363% (mean improvement 344.7 ± 265.1m; p < .001) and peak walking distance (PWD) by 324.4% in the supervised exercise group; COD increased by 30.6% (mean improvement 32.8 ± 57.2 m; p = 0.026) and PWD by 31.5% in the home-based exercise group. Resting ABPI for the total cohort significantly improved from 0.82 ± 0.25 at A1 to 0.88 ± 0.25 at A2 (p = 0.027).

DISCUSSION

A 12-week course of supervised exercise results in significantly greater walking distance outcomes (COD and PWD) than unmonitored home-based exercise. In contrast with previous findings (Lane et al. 2017), this retrospective study demonstrated a significant improvement in resting ABPI with both supervised exercise as well as home-based exercise.

CONCLUSION

A 12-week programme of exercise favourably influenced walking and ABPI outcomes for patients with IC. Both home-based exercise and supervised individualised exercise increased walking distances, but the magnitude of the improvement in walking outcomes was greater in individuals who attended supervised exercise therapy.

Ankle Brachial Pressure Index: An update for the vascular specialist and general practitioner

Objectives

Ankle brachial pressure index (ABPI) is an invaluable tool for assessing the severity of peripheral arterial disease. In addition, it can be used as an independent marker of cardiovascular risk, with a predictive ability similar to the Framingham criteria. Identification of an abnormal ABPI should therefore trigger aggressive cardiac risk factor modulation for a patient. Unfortunately, the significance of abnormal ABPIs is poorly understood within the general medical community. This is compounded by the influence of various comorbidities on accurate measurement of ABPI, potentially leading to a wide variability in readings that need to be considered before interpretation in these patient populations. We aim to address these issues by revealing several common misunderstandings and pitfalls in ABPI measurement, describing accurate methodology, and highlighting patient cohorts in whom additional or alternative approaches may be required.

Methods

We present a narrative review of the role of ABPI in both the community and hospital setting. We have performed a literature review, exploring the validity and reproducibility of methodology for obtaining ABPI, alongside the utility of ABPI in different clinical scenarios.

Results

The measurement of ABPI is often performed incorrectly. Common pitfalls include inadequate patient preparation, failure to obtain the blood pressure from the correct lower limb artery in patients with tibial disease, failure to account for differences in brachial blood pressure between the arms, inappropriately chosen equipment and patient factors such as highly calcified arteries. Standardisation of methodology greatly improves reliability of the test. Exercise ABPI can identify significant peripheral arterial disease in patients with normal resting ABPI. In addition to its role in peripheral arterial disease, ABPI measurement has a role in assessing venous ulcers, entrapment syndromes and injured extremities; conversely, it has a more limited utility in the diabetic population.

Conclusions

A thorough understanding of the correct technique and associated limitations of ABPI measurement is essential in accurately generating and interpreting the data it provides. With this knowledge, the ABPI is an invaluable tool to help manage patients with peripheral arterial disease. Perhaps more importantly, ABPI can be used to identify and risk stratify patients with asymptomatic peripheral arterial disease, itself a major indicator of significant underlying cardiovascular disease. With the emergence of best medical therapy, targeted pharmacotherapy and lifestyle changes can reduce the risk of major cardiovascular events in high-risk patients by approximately 30%, particularly in diabetic patients. Therefore, the utility of ABPI transgresses vascular surgery, with an essential role in general practice and public health.

The burden and characteristics of peripheral arterial disease in patients undergoing amputation in Korle Bu Teaching Hospital, Accra, Ghana

Background

To determine the prevalence of Peripheral Arterial Disease (PAD) and associated risk factors in patients undergoing amputation at the Korle Bu Teaching Hospital (KBTH), Accra, Ghana.

Objectives

A cross- sectional study of all patients undergoing lower extremity amputation at the Department of Surgery, KBTH.

Materials

A coded questionnaire was used to ascertain risk factors for PAD. The Edinburgh Claudication Questionnaire was used to determine symptomatic PAD and a 5 mmHz hand held Summit® Doppler together with an Accoson ® sphygmomanometer was used to determine PAD and its severity.

Method

Clinical diagnosis of symptomatic PAD was made using a symptom-based questionnaire and signs of PAD determined by measuring the ankle brachial pressure index (ABPI) by means of a handheld Doppler and sphygmomanometer. Risk factors were determined using the coded questionnaire and related to the occurrence and severity of PAD.

Results

The prevalence of PAD among recruited participants was 71%. Twenty-eight per cent of participants with PAD in the index limb also showed signs of PAD in the other limb. The diagnosis of PAD was made in 71%, using ABPI, and 13%, using ECQ. Twenty-seven per cent of patient with hypertension, seventeen per cent with diabetes and all patients with hypercholesterolemia were not on any form of medication.

Conclusion

There is a high prevalence of PAD among patients undergoing lower extremity amputation at the KBTH. The majority of PAD patients presented with moderate to severe PAD. Instituting measures to identify and control risk factors of PAD may reduce this high burden.

Funding

Not declared.

Funding source

Authors funded the study.

Evolution of brachytherapy treatment planning to deterministic radiation transport for calculation of cardiac dose

Brachytherapy was among the first methods of radiotherapy and has steadily continued to evolve. Here we present a brief review of the progression of dose calculation methods in brachytherapy to the current state-of-the art computerized methods for heterogeneity correction. We further review the origin and development of the BrachyVision (Varian Medical Systems, Inc., Palo Alto, CA) treatment planning system and evaluate dosimetric results from 12 patients implanted with the strut-assisted volumetric implant (SAVI) applicator (Cianna Medical, Aliso Viejo, CA) for accelerated partial breast irradiation (APBI). Dosimetric results from plans calculated using homogenous and heterogeneous algorithms have been compared to investigate the impact of heterogeneity corrections. Our study showed large percent difference between mean cardiac doses 11.8 ± 6.2% (p = 0.0007) calculated with and without heterogeneity corrections. Our findings are consistent with those of others, indicating an overestimation of the distal dose to organs-at-risk by traditional methods, especially at interfaces between air and tissue.

The importance of accurate methodology in ABPI calculation when assessing lower limb wounds

Recent health economic publications have highlighted the cost of wound care and demonstrated the important role played by community and practice nurses in delivering care. Leg ulcers form a significant proportion of the wounds managed in the community. Data indicates that many patients are managed with no specific diagnosis or without calculation of the ankle brachial pressure index (ABPI), despite care guidelines emphasising the importance of a full assessment including Doppler ABPI calculation in patient management. This article highlights the important role Doppler ABPI plays in patient assessment and describes the methodology, focusing on the importance of correct application of the technique if reliable reproducible results are to be obtained. The rationale for obtaining blood pressure readings from both arms is discussed, and the possible error resulting from reliance on single upper limb blood pressure measurement for both manual and automated ABPI calculation is highlighted and its impact on ABPI calculation illustrated.

Clinical assessment of patients with peripheral arterial disease

Peripheral arterial disease (PAD) describes the clinical manifestations of atherosclerosis affecting the circulation in the legs. The severity of PAD is classified according to symptom severity, time course, and anatomical distribution. The signs and symptoms of PAD reflect the degree of circulatory compromise and whether there has been a gradual reduction in the circulation or an abrupt, uncompensated decrease. Accurate clinical assessment underpins decisions on management strategy and should objectively assess the severity of the ischemia and need for revascularization. Clinical history should discriminate symptoms of PAD from other conditions presenting with leg pain, elucidate cardiovascular risk factors and the effect of symptoms on the patient's quality of life. Clinical examination includes signs of general cardiovascular disease and associated conditions before assessing the circulation and viability of the limb. Palpation of peripheral pulses must be augmented by determination of the ankle brachial pressure index using hand held Doppler. A whole patient approach to management is required and must include modification of cardiovascular risk status as well as dealing with the local circulatory manifestation of PAD.

Chronic venous ulceration of leg associated with peripheral arterial disease: an underappreciated entity in developing country

Chronic venous ulcer can often be associated with asymptomatic peripheral arterial disease (PAD), which usually remains undiagnosed adding significantly to the morbidity of these patients. The Ankle-Brachial Pressure Index (ABPI) is suggested for PAD evaluation. Many PAD studies were conducted in western countries, but there is a scarcity of data on the prevalence of PAD in clinical venous ulcer patient in developing countries. We conducted a study in a tertiary care hospital of eastern part of India to find out the prevalence of PAD in venous ulcer patients, and also to find the sensitivity of ABPI as a diagnostic tool in these patients. We evaluated clinically diagnosed patients with venous ulcer using ABPI and Colour Doppler study for the presence of PAD. Possible associations such as age, sex, body mass index (BMI), smoking, hypertension and atherosclerosis were studied. All results were analysed using the software Statistica version 6. PAD was present in 23 (27·71%) patients. Older age, longer duration, smoking, high BMI and hypertension were found to be significantly associated with PAD. A very strong level of agreement was found between venous Doppler and ABPI. Assessment for the presence of PAD is important in all clinically diagnosed venous ulcer patients. ABPI being a simple, non-invasive outpatient department (OPD)-based procedure, can be routinely used in cases of venous ulcer to find out the hidden cases of PAD even in developing countries.

Ankle brachial pressure index (ABPI): An update for practitioners

Peripheral vascular disease affects some 12%-14% of the general population, and the majority of people with the disease are asymptomatic. The ankle brachial pressure index (ABPI) test is widely used by a diverse range of practitioners (in the community and hospital setting) in order to screen asymptomatic patients, diagnose patients with clinical symptoms, and to monitor patients who have had radiological or surgical intervention. This paper explains the theoretical basis of the ABPI test, as well as the relevance of the common modifications of the test. It explores the background to the quoted normal ranges for the ABPI test. It reviews the large body of literature that has developed on the association between ABPI and cardiovascular risk, as well as ABPI as a predictor for cardiovascular morbidity and mortality, highlighting the evidence that can inform practice. The review looks critically at the limitations of the ABPI test, providing practitioners with an evidence-based update on the importance and challenges of standardizing ABPI methodology. This paper highlights the influence of the key technical aspects of the ABPI test that all practitioners need to consider in order to be able to make more reliable and informed management decisions based on ABPI findings.